Loading...
1/* fs/ internal definitions
2 *
3 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12struct super_block;
13struct file_system_type;
14struct iomap;
15struct iomap_ops;
16struct linux_binprm;
17struct path;
18struct mount;
19struct shrink_control;
20
21/*
22 * block_dev.c
23 */
24#ifdef CONFIG_BLOCK
25extern void __init bdev_cache_init(void);
26
27extern int __sync_blockdev(struct block_device *bdev, int wait);
28
29#else
30static inline void bdev_cache_init(void)
31{
32}
33
34static inline int __sync_blockdev(struct block_device *bdev, int wait)
35{
36 return 0;
37}
38#endif
39
40/*
41 * buffer.c
42 */
43extern void guard_bio_eod(int rw, struct bio *bio);
44extern int __block_write_begin_int(struct page *page, loff_t pos, unsigned len,
45 get_block_t *get_block, struct iomap *iomap);
46
47/*
48 * char_dev.c
49 */
50extern void __init chrdev_init(void);
51
52/*
53 * namei.c
54 */
55extern int user_path_mountpoint_at(int, const char __user *, unsigned int, struct path *);
56extern int vfs_path_lookup(struct dentry *, struct vfsmount *,
57 const char *, unsigned int, struct path *);
58
59/*
60 * namespace.c
61 */
62extern void *copy_mount_options(const void __user *);
63extern char *copy_mount_string(const void __user *);
64
65extern struct vfsmount *lookup_mnt(const struct path *);
66extern int finish_automount(struct vfsmount *, struct path *);
67
68extern int sb_prepare_remount_readonly(struct super_block *);
69
70extern void __init mnt_init(void);
71
72extern int __mnt_want_write(struct vfsmount *);
73extern int __mnt_want_write_file(struct file *);
74extern void __mnt_drop_write(struct vfsmount *);
75extern void __mnt_drop_write_file(struct file *);
76
77/*
78 * fs_struct.c
79 */
80extern void chroot_fs_refs(const struct path *, const struct path *);
81
82/*
83 * file_table.c
84 */
85extern struct file *get_empty_filp(void);
86
87/*
88 * super.c
89 */
90extern int do_remount_sb(struct super_block *, int, void *, int);
91extern bool trylock_super(struct super_block *sb);
92extern struct dentry *mount_fs(struct file_system_type *,
93 int, const char *, void *);
94extern struct super_block *user_get_super(dev_t);
95
96/*
97 * open.c
98 */
99struct open_flags {
100 int open_flag;
101 umode_t mode;
102 int acc_mode;
103 int intent;
104 int lookup_flags;
105};
106extern struct file *do_filp_open(int dfd, struct filename *pathname,
107 const struct open_flags *op);
108extern struct file *do_file_open_root(struct dentry *, struct vfsmount *,
109 const char *, const struct open_flags *);
110
111extern long do_handle_open(int mountdirfd,
112 struct file_handle __user *ufh, int open_flag);
113extern int open_check_o_direct(struct file *f);
114extern int vfs_open(const struct path *, struct file *, const struct cred *);
115extern struct file *filp_clone_open(struct file *);
116
117/*
118 * inode.c
119 */
120extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc);
121extern void inode_add_lru(struct inode *inode);
122extern int dentry_needs_remove_privs(struct dentry *dentry);
123
124extern bool __atime_needs_update(const struct path *, struct inode *, bool);
125static inline bool atime_needs_update_rcu(const struct path *path,
126 struct inode *inode)
127{
128 return __atime_needs_update(path, inode, true);
129}
130
131extern bool atime_needs_update_rcu(const struct path *, struct inode *);
132
133/*
134 * fs-writeback.c
135 */
136extern void inode_io_list_del(struct inode *inode);
137
138extern long get_nr_dirty_inodes(void);
139extern void evict_inodes(struct super_block *);
140extern int invalidate_inodes(struct super_block *, bool);
141
142/*
143 * dcache.c
144 */
145extern struct dentry *__d_alloc(struct super_block *, const struct qstr *);
146extern int d_set_mounted(struct dentry *dentry);
147extern long prune_dcache_sb(struct super_block *sb, struct shrink_control *sc);
148extern struct dentry *d_alloc_cursor(struct dentry *);
149
150/*
151 * read_write.c
152 */
153extern int rw_verify_area(int, struct file *, const loff_t *, size_t);
154
155/*
156 * pipe.c
157 */
158extern const struct file_operations pipefifo_fops;
159
160/*
161 * fs_pin.c
162 */
163extern void group_pin_kill(struct hlist_head *p);
164extern void mnt_pin_kill(struct mount *m);
165
166/*
167 * fs/nsfs.c
168 */
169extern const struct dentry_operations ns_dentry_operations;
170
171/*
172 * fs/ioctl.c
173 */
174extern int do_vfs_ioctl(struct file *file, unsigned int fd, unsigned int cmd,
175 unsigned long arg);
176extern long vfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
177
178/*
179 * iomap support:
180 */
181typedef loff_t (*iomap_actor_t)(struct inode *inode, loff_t pos, loff_t len,
182 void *data, struct iomap *iomap);
183
184loff_t iomap_apply(struct inode *inode, loff_t pos, loff_t length,
185 unsigned flags, struct iomap_ops *ops, void *data,
186 iomap_actor_t actor);
187
188/* direct-io.c: */
189int sb_init_dio_done_wq(struct super_block *sb);
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/* fs/ internal definitions
3 *
4 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8struct super_block;
9struct file_system_type;
10struct iomap;
11struct iomap_ops;
12struct linux_binprm;
13struct path;
14struct mount;
15struct shrink_control;
16struct fs_context;
17struct pipe_inode_info;
18struct iov_iter;
19struct mnt_idmap;
20
21/*
22 * block/bdev.c
23 */
24#ifdef CONFIG_BLOCK
25extern void __init bdev_cache_init(void);
26#else
27static inline void bdev_cache_init(void)
28{
29}
30#endif /* CONFIG_BLOCK */
31
32/*
33 * buffer.c
34 */
35int __block_write_begin_int(struct folio *folio, loff_t pos, unsigned len,
36 get_block_t *get_block, const struct iomap *iomap);
37
38/*
39 * char_dev.c
40 */
41extern void __init chrdev_init(void);
42
43/*
44 * fs_context.c
45 */
46extern const struct fs_context_operations legacy_fs_context_ops;
47extern int parse_monolithic_mount_data(struct fs_context *, void *);
48extern void vfs_clean_context(struct fs_context *fc);
49extern int finish_clean_context(struct fs_context *fc);
50
51/*
52 * namei.c
53 */
54extern int filename_lookup(int dfd, struct filename *name, unsigned flags,
55 struct path *path, struct path *root);
56int do_rmdir(int dfd, struct filename *name);
57int do_unlinkat(int dfd, struct filename *name);
58int may_linkat(struct mnt_idmap *idmap, const struct path *link);
59int do_renameat2(int olddfd, struct filename *oldname, int newdfd,
60 struct filename *newname, unsigned int flags);
61int do_mkdirat(int dfd, struct filename *name, umode_t mode);
62int do_symlinkat(struct filename *from, int newdfd, struct filename *to);
63int do_linkat(int olddfd, struct filename *old, int newdfd,
64 struct filename *new, int flags);
65
66/*
67 * namespace.c
68 */
69extern struct vfsmount *lookup_mnt(const struct path *);
70extern int finish_automount(struct vfsmount *, const struct path *);
71
72extern int sb_prepare_remount_readonly(struct super_block *);
73
74extern void __init mnt_init(void);
75
76int mnt_get_write_access_file(struct file *file);
77void mnt_put_write_access_file(struct file *file);
78
79extern void dissolve_on_fput(struct vfsmount *);
80extern bool may_mount(void);
81
82int path_mount(const char *dev_name, struct path *path,
83 const char *type_page, unsigned long flags, void *data_page);
84int path_umount(struct path *path, int flags);
85
86int show_path(struct seq_file *m, struct dentry *root);
87
88/*
89 * fs_struct.c
90 */
91extern void chroot_fs_refs(const struct path *, const struct path *);
92
93/*
94 * file_table.c
95 */
96struct file *alloc_empty_file(int flags, const struct cred *cred);
97struct file *alloc_empty_file_noaccount(int flags, const struct cred *cred);
98struct file *alloc_empty_backing_file(int flags, const struct cred *cred);
99
100static inline void file_put_write_access(struct file *file)
101{
102 put_write_access(file->f_inode);
103 mnt_put_write_access(file->f_path.mnt);
104 if (unlikely(file->f_mode & FMODE_BACKING))
105 mnt_put_write_access(backing_file_user_path(file)->mnt);
106}
107
108static inline void put_file_access(struct file *file)
109{
110 if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) {
111 i_readcount_dec(file->f_inode);
112 } else if (file->f_mode & FMODE_WRITER) {
113 file_put_write_access(file);
114 }
115}
116
117/*
118 * super.c
119 */
120extern int reconfigure_super(struct fs_context *);
121extern bool super_trylock_shared(struct super_block *sb);
122struct super_block *user_get_super(dev_t, bool excl);
123void put_super(struct super_block *sb);
124extern bool mount_capable(struct fs_context *);
125int sb_init_dio_done_wq(struct super_block *sb);
126
127/*
128 * Prepare superblock for changing its read-only state (i.e., either remount
129 * read-write superblock read-only or vice versa). After this function returns
130 * mnt_is_readonly() will return true for any mount of the superblock if its
131 * caller is able to observe any changes done by the remount. This holds until
132 * sb_end_ro_state_change() is called.
133 */
134static inline void sb_start_ro_state_change(struct super_block *sb)
135{
136 WRITE_ONCE(sb->s_readonly_remount, 1);
137 /*
138 * For RO->RW transition, the barrier pairs with the barrier in
139 * mnt_is_readonly() making sure if mnt_is_readonly() sees SB_RDONLY
140 * cleared, it will see s_readonly_remount set.
141 * For RW->RO transition, the barrier pairs with the barrier in
142 * mnt_get_write_access() before the mnt_is_readonly() check.
143 * The barrier makes sure if mnt_get_write_access() sees MNT_WRITE_HOLD
144 * already cleared, it will see s_readonly_remount set.
145 */
146 smp_wmb();
147}
148
149/*
150 * Ends section changing read-only state of the superblock. After this function
151 * returns if mnt_is_readonly() returns false, the caller will be able to
152 * observe all the changes remount did to the superblock.
153 */
154static inline void sb_end_ro_state_change(struct super_block *sb)
155{
156 /*
157 * This barrier provides release semantics that pairs with
158 * the smp_rmb() acquire semantics in mnt_is_readonly().
159 * This barrier pair ensure that when mnt_is_readonly() sees
160 * 0 for sb->s_readonly_remount, it will also see all the
161 * preceding flag changes that were made during the RO state
162 * change.
163 */
164 smp_wmb();
165 WRITE_ONCE(sb->s_readonly_remount, 0);
166}
167
168/*
169 * open.c
170 */
171struct open_flags {
172 int open_flag;
173 umode_t mode;
174 int acc_mode;
175 int intent;
176 int lookup_flags;
177};
178extern struct file *do_filp_open(int dfd, struct filename *pathname,
179 const struct open_flags *op);
180extern struct file *do_file_open_root(const struct path *,
181 const char *, const struct open_flags *);
182extern struct open_how build_open_how(int flags, umode_t mode);
183extern int build_open_flags(const struct open_how *how, struct open_flags *op);
184struct file *file_close_fd_locked(struct files_struct *files, unsigned fd);
185
186long do_ftruncate(struct file *file, loff_t length, int small);
187long do_sys_ftruncate(unsigned int fd, loff_t length, int small);
188int chmod_common(const struct path *path, umode_t mode);
189int do_fchownat(int dfd, const char __user *filename, uid_t user, gid_t group,
190 int flag);
191int chown_common(const struct path *path, uid_t user, gid_t group);
192extern int vfs_open(const struct path *, struct file *);
193
194/*
195 * inode.c
196 */
197extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc);
198int dentry_needs_remove_privs(struct mnt_idmap *, struct dentry *dentry);
199bool in_group_or_capable(struct mnt_idmap *idmap,
200 const struct inode *inode, vfsgid_t vfsgid);
201
202/*
203 * fs-writeback.c
204 */
205extern long get_nr_dirty_inodes(void);
206void invalidate_inodes(struct super_block *sb);
207
208/*
209 * dcache.c
210 */
211extern int d_set_mounted(struct dentry *dentry);
212extern long prune_dcache_sb(struct super_block *sb, struct shrink_control *sc);
213extern struct dentry *d_alloc_cursor(struct dentry *);
214extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *);
215extern char *simple_dname(struct dentry *, char *, int);
216extern void dput_to_list(struct dentry *, struct list_head *);
217extern void shrink_dentry_list(struct list_head *);
218extern void shrink_dcache_for_umount(struct super_block *);
219extern struct dentry *__d_lookup(const struct dentry *, const struct qstr *);
220extern struct dentry *__d_lookup_rcu(const struct dentry *parent,
221 const struct qstr *name, unsigned *seq);
222extern void d_genocide(struct dentry *);
223
224/*
225 * pipe.c
226 */
227extern const struct file_operations pipefifo_fops;
228
229/*
230 * fs_pin.c
231 */
232extern void group_pin_kill(struct hlist_head *p);
233extern void mnt_pin_kill(struct mount *m);
234
235/*
236 * fs/nsfs.c
237 */
238extern const struct dentry_operations ns_dentry_operations;
239
240/*
241 * fs/stat.c:
242 */
243
244int getname_statx_lookup_flags(int flags);
245int do_statx(int dfd, struct filename *filename, unsigned int flags,
246 unsigned int mask, struct statx __user *buffer);
247
248/*
249 * fs/splice.c:
250 */
251ssize_t splice_file_to_pipe(struct file *in,
252 struct pipe_inode_info *opipe,
253 loff_t *offset,
254 size_t len, unsigned int flags);
255
256/*
257 * fs/xattr.c:
258 */
259struct xattr_name {
260 char name[XATTR_NAME_MAX + 1];
261};
262
263struct xattr_ctx {
264 /* Value of attribute */
265 union {
266 const void __user *cvalue;
267 void __user *value;
268 };
269 void *kvalue;
270 size_t size;
271 /* Attribute name */
272 struct xattr_name *kname;
273 unsigned int flags;
274};
275
276
277ssize_t do_getxattr(struct mnt_idmap *idmap,
278 struct dentry *d,
279 struct xattr_ctx *ctx);
280
281int setxattr_copy(const char __user *name, struct xattr_ctx *ctx);
282int do_setxattr(struct mnt_idmap *idmap, struct dentry *dentry,
283 struct xattr_ctx *ctx);
284int may_write_xattr(struct mnt_idmap *idmap, struct inode *inode);
285
286#ifdef CONFIG_FS_POSIX_ACL
287int do_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
288 const char *acl_name, const void *kvalue, size_t size);
289ssize_t do_get_acl(struct mnt_idmap *idmap, struct dentry *dentry,
290 const char *acl_name, void *kvalue, size_t size);
291#else
292static inline int do_set_acl(struct mnt_idmap *idmap,
293 struct dentry *dentry, const char *acl_name,
294 const void *kvalue, size_t size)
295{
296 return -EOPNOTSUPP;
297}
298static inline ssize_t do_get_acl(struct mnt_idmap *idmap,
299 struct dentry *dentry, const char *acl_name,
300 void *kvalue, size_t size)
301{
302 return -EOPNOTSUPP;
303}
304#endif
305
306ssize_t __kernel_write_iter(struct file *file, struct iov_iter *from, loff_t *pos);
307
308/*
309 * fs/attr.c
310 */
311struct mnt_idmap *alloc_mnt_idmap(struct user_namespace *mnt_userns);
312struct mnt_idmap *mnt_idmap_get(struct mnt_idmap *idmap);
313void mnt_idmap_put(struct mnt_idmap *idmap);
314struct stashed_operations {
315 void (*put_data)(void *data);
316 int (*init_inode)(struct inode *inode, void *data);
317};
318int path_from_stashed(struct dentry **stashed, struct vfsmount *mnt, void *data,
319 struct path *path);
320void stashed_dentry_prune(struct dentry *dentry);